feat(workflow): Github bot added

[rootxrishabh]

Purpose of PR?:
This PR introduces a GitHub workflow bot for the following purposes

• Checking for failing checks
• Checking for stale PRs
• Assigning reviewers
• Greeting the issue creator
  Fixes #
  Making a github bot to improve our repo's workflow #1082
  Does this PR introduce a breaking change?
  No
  If the changes in this PR are manually verified, list down the scenarios covered::

Additional information for reviewer? :
Mention if this PR is part of any design or a continuation of previous PRs

Checklist:

• Bug fix. Fixes #
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• This change requires a documentation update
• PR Title follows the convention of <type>(<scope>): <subject>
• Commit has unit tests
• Commit has integration tests

[DelusionalOptimist]

Hey @rootxrishabh! Let us know if you need help with anything in carrying this PR forward : )

[rootxrishabh]

Hey @DelusionalOptimist, to my understanding assigning reviewers and checking for stale PRs functionality isn't working due to an issue with actions itself, While testing whenever I made a PR using a fork(made a friend do it) it would give permission errors. Would love to discuss any workarounds or suggestions that you might have.
For reference